This invention relates to a filtering centrifuge. More specifically, this invention relates to a filtering centrifuge with a mechanism for removing cake from filter media disposed along the inner surface of a rotatable filter basket. This invention also relates to an associated method for cleaning a filtering type centrifuge of cake deposited along filter media in the centrifuge.
A filtering centrifuge generally comprises a rotating perforated drum commonly referred to as a basket. This basket is lined with pervious filter media. During operation of the centrifuge, the basket is rotated while a slurry of solids suspended in a liquid is introduced into the basket. The rotation of the basket generates a multiplied centrifugal force which flings the slurry outwardly onto the filter media. The solids portion of the slurry is captured by the filter media and is deposited as a cake layer thereon, while the liquid portion of the slurry drains through the filter media and out of the basket through the perforations therein.
Once the processing of the captured solids is complete, in many cases the solids are automatically discharged by introducing a deflector blade or plow into the captured solids (filter cake) as the basket slowly rotates. The cake is thereby deflected out through an opening in the bottom of the basket. In executing this operation, the plow is stopped short of contacting the filter media to prevent damage thereto. This procedure results in a thin layer of undischarged cake being left in the basket. This undischarged layer of cake is referred to as "heel."